Grape Seed Polyphenols Ameliorated Dextran Sulfate Sodium-Induced Colitis via Suppression of Inflammation and Apoptosis.

Ulcerative colitis (UC) is an inflammatory bowel disease. Its onset is typically gradual, usually followed by periods of spontaneous remission and subsequent relapses. Grape seed polyphenols (GSP), a natural product extracted from grape seeds, have strong anti-inflammatory functions.In this study, we investigated whether GSP has an inhibitory effect on UC and its related mechanism or not.We induced UC by 2.5% dextran sulfate sodium (DSS) and GSP at different doses (500 and 750 mg/kg body weight per day) was administrated to the mice by gavage. Body weight, diarrhea, and bloody stool were recorded every day to evaluate disease activity index. Hemotoxylin-eosin staining and immunohistochemical staining were used to identify the histological damages and inflammatory infiltration in colon tissues. Real-time polymerase chain reaction was used to evaluate mRNA expression of interleukin (IL)-6, IL-1β, and tumor necrosis factor (TNF)-α and the expression of phosphorylated-signal transducer and activator of transcription 3 (STAT3) and STAT3 were assessed by western blot. The immunofluorescent assay was used to evaluate the apoptosis of intestinal epithelial cells (IECs).GSP could alleviate the loss of body weight, diarrhea, bloody stool, the mucosal damage, and inflammatory infiltration. GSP could also downregulate the mRNA expression of inflammatory cytokines IL-6, IL-1β, and TNF-α as well as the phosphorylation of STAT3 and ameliorate the apoptosis of IECs.Our study suggests that GSP has protective effects against DSS-induced UC, which may through suppression of inflammation and apoptosis.